Path: cactus.org!milano!cs.utexas.edu!uunet!mcsun!uknet!cam-cl!cam-cl!rja14 From: rja14@cl.cam.ac.uk (Ross Anderson) Newsgroups: sci.crypt Subject: Re: well braid Message-ID: <1992Aug18.105437.4617@cl.cam.ac.uk> Date: 18 Aug 92 10:54:37 GMT References: <13989@elevia.uniforum.qc.ca> Sender: news@cl.cam.ac.uk (The news facility) Reply-To: rja14@cl.cam.ac.uk (Ross Anderson) Organization: U of Cambridge Computer Lab, UK Lines: 20 -------- (20 lines) More? [ynq] In <13989@elevia.uniforum.qc.ca>, alain@elevia.uniforum.qc.ca (W.A.Simon) writes: > The proposed system works by multiplexing (braiding) two or more bit > streams. Depending on the value of key bits, the next bit of output > is taken from one or the other input. Something similar has been around in the world of stream ciphers since about 1980. It was demolished in `Solving a class of stream ciphers', Cryptologia vol XIV no 3 (July 1990) pp 285 - 288. As far as I can see, your system will have to be modified to withstand this kind of attack. Hope this helps Ross